The present invention relates to a plasma processing method and apparatus for carrying out plasma processing on a portion of a surface of an object to be processed, and in particular, to a plasma processing method and apparatus for carrying out plasma processing for processing a linear portion on an object to be processed.
In general, when an object to be processed represented by a substrate on the surface of which a thin film is formed is subjected to a patterning process, a resist process is used. One example of the process is shown in FIGS. 15A through 15D. In FIGS. 15A through 15D, first of all, a photosensitive resist 34 is coated on the surface of an object 33 to be processed (FIG. 15A). Next, by carrying out exposure by means of an exposure apparatus and thereafter carrying out development, the resist 34 can be patterned into the desired shape (FIG. 15B). Then, by placing the object 33 in a vacuum vessel, generating a plasma in the vacuum vessel and subjecting the object 33 to an etching process using the resist 34 as a mask; the surface of the object 33 is patterned into the desired shape (FIG. 15C). Finally, by removing the resist 34 by means of an oxygen plasma, an organic solvent, or the like, the processing is completed (FIG. 15D).
The aforementioned resist process, which has been suitable for accurately forming a minute pattern, has come to play an important role in manufacturing electronic devices such as semiconductors. However, there is a drawback that the process is complicated.
Accordingly, there is examined a new processing method that uses no resist process. As one example, there is being proposed a plasma processing apparatus equipped with a microplasma source 99 as shown in FIG. 16A. With regard to the construction described as above, for example, a system for flowing gas in a linear direction is described in U.S. patent application Ser. No. 10/365,449 that has not yet been laid open.
Moreover, a system for applying an electric field across two electrodes is described in Unexamined Japanese Patent Publication No. 09-49083.
However, in the above-mentioned plasma processing apparatus, there is an issue that a processing speed is largely varied in two arbitrary portions in the linear direction (the uniformity of processing is poor) when a distance between the plasma source and the object to be processed is not uniform in the linear direction. For example, there is an issue that, when a plasma source 99 is inclined along the linear direction with respect to a thin plate 97 that is the object to be processed as shown in FIGS. 16A and 16B, a plasma 91 is concentrated on a portion where the distance between the plasma source 99 and the object 97 to be processed is small, failing in achieving plasma processing uniform in the linear direction.